February 27, 2004 - The Chronicle of Higher Education (US)
Ecstasy Agonistes
A Retracted Study On A Controversial Substance Raises Questions
About The Reliability Of Government-Sponsored Research On Drugs
By Thomas Bartlett
Until recently, Ecstasy had been very good to George A. Ricaurte.
An associate professor of neurology at the Johns Hopkins University,
Dr. Ricaurte is the nation's most prominent researcher on methylenedioxymethamphetamine,
or MDMA, the chemical name for Ecstasy, a drug that produces
feelings of intense euphoria, heightened sociability, and enhanced
sensations like touch. His research in the mid-1980s was the
first to suggest that the drug might be damaging to the serotonin
system, which is important in regulating mood, sleep, appetite,
and other functions. He has also received nearly $10-million
in federal funds in the last seven years, and some of his research
results have become key building blocks in the government's much-ballyhooed
"war on drugs."
In an article published in the September 27, 2002, issue of
the journal Science, Dr. Ricaurte (pronounced ri-CAR-tay) launched
another salvo in support of that war. His article warned of new
dangers attached to the use of Ecstasy, including the risk of
severe brain damage and debilitating neurological diseases, such
as Parkinson's-even from just one night of using the drug.
It was sensational and frightening news. Within days, Dr.
Ricaurte's findings were printed in scores of newspapers around
the world and repeated on television.
But that particular alarm about Ecstasy turned out to be false.
A serious and almost unbelievable mistake-the primates in
the study were injected not with Ecstasy, but with methamphetamine-negated
both the study and its startling results.
Almost exactly a year later, Dr. Ricaurte retracted the article.
That is the way science works.
A scientist makes a mistake, discovers it, and issues a retraction.
End of story.
But this was not just any article, and Dr. Ricaurte is not
just any researcher. His previous work had already attracted
plenty of critics. Many of them are leading researchers themselves,
who contend that Dr. Ricaurte's studies have been flawed and
biased.
Specifically, some accuse him of overstating the dangers of
Ecstasy to please his government backers.
The fallout from the mistake has brought not only Dr. Ricaurte's
reputation into question, but also that of the National Institute
on Drug Abuse, which has supported his research for years. "It
kind of gives science a black eye because people start to question
whether NIDA has an agenda," says Glen R. Hanson, a professor
of pharmacology and toxicology at the University of Utah and
a former director of NIDA.
The retraction has prompted some, like Charles S. Grob, a
professor of psychiatry and pediatrics at the University of California
at Los Angeles School of Medicine and a longtime critic of Dr.
Ricaurte's work, to urge a second look. "The whole thing
about Ricaurte really demands a thorough, objective re-evaluation
of the whole record of MDMA research going back 15 years,"
he says.
At the least, say some researchers, future Ecstasy studies
may be ignored or viewed more skeptically by the public. "An
Ecstasy user is not going to believe any statement by a scientist,"
says Stephen J. Kish, head of the human-neurochemical-pathology
laboratory at Canada's Center for Addiction and Mental Health.
"Whether they did before, I'm not certain, but it's now
going to be much more difficult."
Holes in the Research
It is not surprising that Dr. Ricaurte's 2002 claims inspired
such a strong reaction.
The drug, first synthesized by the German pharmaceutical company
Merck in 1912, has been used by millions of people for more than
20 years, and inspired a popular music and fashion subculture.
Many former and current users wondered if the damage had already
been done. But the 2002 study was not the first time that his
work had landed in the public spotlight. Another article by Dr.
Ricaurte, published in 1998, became the centerpiece of a provocative
anti-Ecstasy campaign paid for by NIDA. In the study, Dr. Ricaurte
scanned the brains of Ecstasy users and compared them with nonusers'
brain scans.
In the advertising campaign, two of those images were combined
into a single image that the drug-abuse agency used on its Web
site and printed on posters and postcards.
The left half of the image is labeled "plain brain"
and appears healthy and vibrant.
The image on the right, which is labeled "brain after
Ecstasy" is much darker. An entire chunk of the organ is
missing, as if the drug had eaten away part of the gray matter.
The compelling campaign seemed to prove that Ecstasy could
cause severe, long-term brain damage. But was its message-based
on Dr. Ricaurte's research-accurate?
A German study published last year using similar methods arrived
at a very different result.
As in Dr. Ricaurte's study, a radioactive marker was used
to tag serotonin neurons in the brains of human subjects, using
Positron Emission Tomography, or PET, scans.
Recent users of Ecstasy and nonusers were scanned.
Instead of finding massive reductions in the number of serotonin
neurons, as Dr. Ricaurte reported, the loss was small-about 4
to 5 percent.
And when the German researchers looked at those who had not
used the drug recently, they found no decrease at all. There
were no holes.
"I've been on record saying [Dr. Ricaurte's study] was
terribly flawed and should not have been published," says
Mr. Kish, who is also a professor of psychiatry and pharmacology
at the University of Toronto. In November Mr. Kish published
an article that highlights the contradictory results of the two
studies.
In it, he also argues that there is little evidence that Ecstasy
leads to Parkinson's disease.
Others, like Marc Laruelle, an associate professor of psychiatry
and radiology at Columbia University and a specialist in PET
scans, agree that Dr. Ricaurte's study was inaccurate.
In December The New York Times reported that two of
Dr. Ricaurte's former subjects said they had been encouraged
by a research assistant to lie about their past drug use and
that they were mistreated during experiments. Dr. Ricaurte has
defended his methods and called the use of heroin by a subject
days before being tested "unfortunate." He stands by
his 1998 article and says that improvements in technology account
for the large discrepancy between the two studies.
But even Dr. Ricaurte has doubts about the "brain after
Ecstasy" image used by NIDA. He says he mentioned once to
an official at the drug-abuse institute that the image was of
"poor quality" but didn't pursue the matter.
Asked why he didn't insist that it be corrected, Dr. Ricaurte
at first says it was not his concern. When pressed, he concedes,
"Maybe I should have picked up the phone and complained."
The image, once featured prominently on NIDA's Web site, has
been removed.
Monkeys and Mistakes
The risks that Dr. Ricaurte examined in his retracted 2002
article in Science were different from those he had explored
before.
While the bulk of previous research had focused on serotonin,
this new study examined MDMA's effect on dopamine, a neurotransmitter
linked to emotion and movement, among other functions.
For years, studies had suggested that MDMA affected only serotonin
neurons.
Many researchers felt sure that it did not damage dopamine
neurons. Dr.
Ricaurte decided to test that notion.
In his retracted article, he describes how five squirrel monkeys
were given three doses-with three hours between each dose-of
what turned out to be methamphetamine.
One of the monkeys had trouble walking after the second dose,
so researchers did not administer a third. Another monkey died
within hours of receiving the third dose, a victim of hyperthermia,
or overheating.
Brain scans of the three monkeys that had tolerated the drug
without apparent difficulty showed massive reductions in dopamine
neurons.
Dr. Ricaurte later performed the same experiment on five baboons,
again apparently mistakenly administering methamphetamine instead
of MDMA. As in the first experiment, one of the primates died
and the others suffered severe damage to their dopamine systems.
The project took about two years, according to Dr. Ricaurte.
He argues that researchers who say he rushed his results into
publication before thoroughly testing them are "uninformed."
In an e-mail message, Dr. Ricaurte wrote, "We reject the
notion that, due to our experience and knowledge of the literature,
we should have concluded that there was some sort of error."
Such explanations have done little to satisfy critics.
Dr. Hanson, who was interim director of NIDA at the time of
the study, was suspicious of the results from the beginning.
"I had a chance to talk to him, and I said, 'George, we
never see this. Where is this coming from?'" Dr. Hanson
says. "And he said, 'Well, the dosing paradigm is different
and there are some subtle differences and maybe there is just
this little window that you don't see unless you do it exactly
right.'"
Dr. Hanson was not persuaded. "I just said I really need
to see this in more animals," he says. "And you always
like to see it done in another lab."
Because of Dr. Hanson's doubts, the drug-abuse institute,
which had given Dr. Ricaurte $1.3-million to carry out the research,
did not publicize his results.
There was no press release, no mention on its Web site. Dr.
Hanson says that while some have used the study to accuse NIDA
of bias, "the irony is we totally stepped back from it because
we wanted to see it replicated somewhere else."
One of the red flags for Dr. Hanson and others was the deaths
from hyperthermia of two of the 10 primates cited in the article.
Deaths from hyperthermia do occur among Ecstasy users, but
they are extremely rare. The drug can affect the body's ability
to regulate temperature, and there is a risk of hyperthermia,
albeit a small one, in people who are exercising vigorously or
who are dehydrated. A recent British study of Ecstasy-related
deaths in that country showed that most of those who died while
on Ecstasy were taking it with another drug.
Dr. Ricaurte scoffs at the suggestion that the deaths of the
two primates should have alerted him to a problem.
He says that Ecstasy is known to cause hyperthermia and that
because the sample size was small, the high mortality rate was
not significant. Dr. Ricaurte also points out that the paper
made it through the peer-review process at Science. If
the flaws were so obvious, he contends, "Science wouldn't
have published the paper."
Donald Kennedy, editor in chief of Science and a former
president of Stanford University, says that the publication of
the flawed article does not mean that there was a breakdown in
the peer-review process.
How, he argues, could peer reviewers have known about the
drug mix-up? "Sometimes in science, mistakes get made and
you discover ... a paper that on balance, with perfect hindsight,
you wish you hadn't published," he says.
Alan I. Leshner, chief executive officer of the American Association
for the Advancement of Science, which publishes Science,
agrees with Mr. Kennedy's assessment. Mr. Leshner is a former
director of NIDA, and some have speculated that he had a hand
in getting Dr. Ricaurte's paper published -- a charge Mr. Leshner
denies.
He says he was not even aware of the paper before it was published.
He calls the retraction "unfortunate" but doesn't believe
it should end Dr. Ricaurte's career. "I don't think he should
be tarnished for a mistake that he very rapidly retracted,"
says Mr. Leshner.
Researchers like Mr. Kish, however, are less willing to let
Science or Dr. Ricaurte off the hook. "How could Science
accept an article purporting to show that Ecstasy causes dopamine
neuron damage in monkeys without having mentioned in the article
that two human studies have been conducted in which there was
no evidence that Ecstasy caused the same type of brain damage?"
he says.
Dr. Ricaurte says he was aware of the studies showing no effect
on dopamine and noted in the article that in previous research
Ecstasy had been shown to affect only serotonin neurons.
He says it was not necessary to cite the other research because
the dosing regime-the frequency with which the primates were
injected with Ecstasy -- had not been attempted in this way before,
under these conditions. It was possible, Dr. Ricaurte says, that
this dosing regime could account for the unusual results.
And yet, long before he acknowledged there had been a mistake,
others in the field voiced skepticism. In fact, four months before
the retraction, Rick Doblin, president of the Multidisciplinary
Association for Psychedelic Studies, which supports research
on the benefits of drugs like Ecstasy and marijuana, had a letter
published in Science questioning Dr. Ricaurte's results.
Dr. Ricaurte responded in the same issue, dismissing Mr. Doblin's
concerns.
When that letter was published, Dr. Ricaurte says, he was
trying to determine why he had been unable to replicate the results
of his earlier experiments. The following month, he wrote to
his backers at NIDA, telling them that the primates had been
injected with methamphetamine, not MDMA. He blamed the error
on "mislabeled drug bottles" from the supplier of the
drug, RTI International. In the report to NIDA, he wrote that
tests showed that bottles from the company labeled MDMA had contained
methamphetamine, and vice versa. (A spokesman for RTI denies
that the company mixed up the drugs, but offers no additional
details.)
Dr. Grob, who has battled Dr. Ricaurte in public for years,
has trouble believing that explanation. "How the hell could
he have mixed up drugs?" says Dr. Grob. "It's unheard
of. Where's the precedent for people doing this level research,
of this supposed caliber, where they are mixing up drugs?"
He goes on to call the retraction "one of the more bizarre
episodes in the history of science."
The Straight Dope
So what do we know for sure about Ecstasy?
After it was created -- apparently by accident -- in 1912,
MDMA mostly disappeared from view for the next 65 years.
It re-emerged in the 1970s when psychotherapists found that
it helped patients relax and be more open.
In the early 1980s, MDMA moved out of the therapist's office
and into the streets, acquiring the sexier name of Ecstasy. It
became available for sale legally in some bars. At one point,
tablets could even be ordered by telephone from a company in
Texas.
That all changed in 1985 when Ecstasy was made illegal even
for psychotherapy. That decision remains controversial, and Ecstasy
advocates argue that it was banned before there was any evidence
that the drug was dangerous.
Indeed, the first studies definitively linking MDMA to the
damage of serotonin neurons came only after the drug was declared
illegal.
One of those pioneering studies was the work of a young researcher
named George Ricaurte.
In those early years, Dr. Ricaurte had a close working relationship
with Mr. Doblin, a believer in the therapeutic uses of Ecstasy
who nevertheless helped arrange financing and volunteers for
Dr. Ricaurte's research. "I felt that those of us who were
looking into the benefits should also be at the forefront of
looking into the risks," says Mr. Doblin.
That working relationship broke down eventually as, in Mr.
Doblin's view, his colleague began reporting his results selectively-trumpeting
Ecstasy's harmful effects, and leaving out contradictory data.
That Ecstasy can damage serotonin neurons in animals is beyond
question.
What is debatable is at what dose that damage occurs, whether
the damage is permanent, and if the damage occurs in humans.
There is evidence suggesting that, at low enough doses, Ecstasy
does not cause damage to the brain, according to Mr. Doblin.
He says Dr. Ricaurte has consistently ignored and suppressed
evidence of this "no-effect level."
That isn't so, according to Dr. Ricaurte. He says a study
in squirrel monkeys did produce such results, but that there
were good reasons not to publish them. "I discussed these
data with Rick Doblin on numerous occasions and explained that
until these negative data were fleshed out by conducting full
dose-ranging studies, they would never be accepted by a peer-reviewed
journal," he wrote in an e-mail message.
Besides, Dr. Ricaurte argues, the doses were much lower than
what people normally take. "I think it's fair to say that
if there is a margin of safety, it appears to be a narrow one,"
he says. As for the potential therapeutic benefits of the drug,
Dr. Ricaurte says they are not his concern. "I'm a neurologist,"
he says. "What I can speak to are the risks. Period."
Collateral Damage
The effect of the retraction on Dr. Ricaurte's career is still
unclear.
A spokesman for Johns Hopkins says the university has taken
no action against him because it was determined that the drug
mix-up was not his fault.
He continues to receive grants from NIDA, but some researchers,
including Dr. Grob, doubt that his professional reputation can
ever recover.
"I don't think he shot himself in the foot. I think he
shot his whole foot off," says Dr. Grob. Dr. Ricaurte argues
that the retraction should bolster his credibility. "Anybody
who looks at this current situation would see that here is a
scientist who recognized an error and immediately did everything
in his power to correct the scientific record as quickly as possible,"
he says. Dr. Ricaurte continues to research the possibility that
MDMA harms the dopamine system.
Larger questions about the future of Ecstasy research-and
its public reception-remain open. Martha Rosenbaum, who has also
received NIDA grants to study Ecstasy, says Dr. Ricaurte's studies
have contributed to a steady stream of misinformation about the
drug that has led to fear-driven legislation. For instance, a
bill recently passed by Congress allows the government to prosecute
the owners of establishments where drugs like Ecstasy are used.
"I'm now convinced that any information coming out of
the government is suspect," says Ms. Rosenbaum, who is a
staff member at the Drug Policy Alliance, which opposes current
drug policy.
The controversy comes at a time when researchers like Marc
Laruelle at Columbia believe that they are on the brink of understanding
how Ecstasy affects the brain.
A new, more accurate radioactive marker is being used that
scientists say will produce much more reliable brain scans. "I
think it's very important that scientists behave in a way that's
going to increase the trust of the public," says Dr. Laruelle.
Last month a study into the therapeutic possibilities of Ecstasy
sponsored by Mr. Doblin's organization was given final government
approval. His goal is to make MDMA into a prescription medicine
for the treatment of post-traumatic stress disorder.
"We've got megamillions going into the demonization of
Ecstasy," Mr. Doblin says, "and all we need is $5-million
to do the clinical trials that will be necessary to provide the
data to decide if this drug will be a helpful medicine to many,
many people."
The new director of NIDA, Nora D. Volkow, worries that the
retraction has sent the message that Ecstasy has been proved
harmless, which is not true. She says she is committed to making
sure that the information the agency disseminates is as accurate
as possible. "The question that comes to light is, why has
this attracted so much attention?" she says. "And I
think perhaps it's because some people are exaggerating the adverse
effects of drugs."
KEY MOMENTS IN ECSTASY RESEARCH
1912: Methylenedioxymethamphetamine, or MDMA, is accidentally
discovered by the German pharmaceutical company Merck.
Late 1970s: Some psychotherapists begin administering the
drug to help their patients relax and communicate more freely.
1985: At the urging of the U.S. Drug Enforcement Administration,
the drug, which is being used recreationally and is now called
Ecstasy, is banned.
1988: George A. Ricaurte, a researcher at the Johns Hopkins
University, publishes one of the first studies linking Ecstasy
to damage of serotonin neurons, which help regulate mood.
1998: Dr. Ricaurte publishes another study of the effects
of Ecstasy on the brain.
2000: The National Institute on Drug Abuse uses Dr. Ricaurte's
1998 study as the centerpiece of a campaign against the drug,
distributing 740,000 postcards advertising its ill effects.
September 2002: Dr. Ricaurte publishes his paper "Severe
dopaminergic neurotoxicity in primates after a common recreational
dose of MDMA" in Science, saying that Ecstasy causes severe
damage to the dopamine systems of primates.
March 2003: A German study is published that challenges Dr.
Ricaurte's 1998 findings.
June 2003: In response to a letter published in Science
questioning his results, Dr. Ricaurte defends his study.
July 2003: Dr. Ricaurte writes to his backers at NIDA informing
them of his inability to replicate the results and his suspicions
that bottles labeled MDMA actually contained methamphetamine.
September 2003: Nearly a year after its publication, Dr. Ricaurte
retracts his 2002 paper.
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